ZURICH (Reuters) - Credit Suisse's chairman warned that a long-running tax dispute with the United States over hidden Swiss bank accounts could easily escalate and spill over to rivals if not settled.

"What looks to be a painful solution at first glance is better for everyone than none at all," Urs Rohner was quoted as telling the Neue Zuercher Zeitung daily on Tuesday.

Rohner's comments come as the Swiss government said it hopes it is nearing a deal with U.S. authorities over Swiss banks accused of helping wealthy Americans evade billions of dollars of tax.

Rohner suggested a settlement still hangs in the balance.

"Should the efforts to settle fail after nearly three years of intense negotiating, it could lead to an escalation of the fight. I can only warn of this," Rohner said.

Credit Suisse is one of roughly a dozen banks being targeted directly by U.S. authorities following a landmark $780 million settlement with UBS in 2009 for helping Americans evade taxes.

The UBS deal, coupled with scores of wealthy Americans who have come clean to the Internal Revenue Service under a series of amnesties, has given U.S. authorities ample information to pursue a second wave of Swiss banks.